My old Pentium III 800MHz died a few days ago, so now put the original Pentium III 600MHz in. Immediately I ran into the same problem that I had before with the P3 600MHz, mouse lock ups. Every two minutes, the mouse will freeze. I have to shake the mouse, and click all the buttons for it to unlock.

This problem only seems to happen with this processor. Can anyone explain why?

Yes, I realize this is an old computer. But it runs just fine for the programs my six year old son uses.

Changing the CPU shouldn't have any effect on the mouse. Unless you knocked something loose when you swapped CPUs?

Have you determined why your "old Pentium III 800MHz died a few days ago"?? That info *may* be helpful.

Have you tried another mouse?

It's not a problem with the mouse. I have already tried two different mouses. Again, I suspect this is an issue with the processor (600MHz) because I had this issue two years ago when I used it. With the 800MHz processor, I never had this problem.

The 800MHz P3 processor died due to a power surge (even though I am using a surge protector). Regardless of whether or not any other hardware was damaged, it would not explain why I had this problem before.

Right now, I am guessing the high CPU loads is causing interrupts in the data signals being sent from the PS/2 inputs. The only way to 'revive' the mouse is to click and move it rapidly, which makes reasonable sense to my suspicion.

How do you know it's not the psu that is damaged from the serge or even your motherboard?